Bosch Washer Error Code dr:18

The dr:18 code means the motor control system detected a peak voltage level that was too high during operation. This points to a fault within the motor control board, which regulates power delivery to the drive motor. The machine shuts down when this condition is detected to prevent further electrical damage. Diagnostic test P4 is used to confirm the fault before any parts are replaced.

No, you should not continue running the washer while this code is active. The dr:18 fault indicates an uncontrolled voltage spike in the motor control system, and continued operation could cause additional damage to the motor, the control board, or other electrical components. The machine will typically refuse to complete a cycle until the fault is resolved, which is a built-in protection feature.

A power reset may temporarily clear the displayed code, but it will not resolve the underlying fault. Because dr:18 is caused by a hardware condition in the motor control board, the voltage spike issue will persist and the code will return once the washer attempts to run again. A proper repair requires running diagnostic test P4 and addressing the root cause, which is most commonly a faulty motor control board.

Diagnosing and repairing dr:18 requires running test P4 in the washer's service diagnostic mode, which involves accessing internal components and understanding the results. If you are comfortable working with appliance electronics and can safely access the motor control board, inspecting wiring connections is a reasonable starting point. However, replacing the motor control board itself is a moderately advanced repair and involves handling high-voltage components, so many owners choose to have a technician handle it.

Repair costs depend on whether the motor control board needs replacement. A new motor control board for a Bosch washer typically costs in the range of $150 to $350 for the part alone. If you hire a technician, labor charges will add another $80 to $150 or more depending on your area. If the issue turns out to be a wiring harness problem, the repair cost can be significantly lower.